Background error modelling: climatological flow-dependence

Size: px
Start display at page:

Download "Background error modelling: climatological flow-dependence"

Transcription

1 Background error modelling: climatological flow-dependence Yann MICHEL NCAR/MMM/B Meeting 16 th April Introduction 2 A new estimate of lengthscales 3 Climatological flow-dependence Yann MICHEL B modelling: climatological flow-dependence 1

2 Background error modelling: climatological flow-dependence Spectral formulations of the B matrix allow: three-dimensional grid point background error σ b ; good representation the average spatial structure of analysis increments. But they are restricted to homogeneous isotropic horizontal analysis increments (for CV); homogeneous structure of vertical correlation (for CV). Gridpoint formulations They allow to relax those assumptions: EOF decomposition can be local; recursive filters can be applied with varying lengthscales. Yann MICHEL B modelling: climatological flow-dependence 2

3 Background error modelling: climatological flow-dependence However currently gen_be/wrf-var do not make benefit of this! We end up with the worse covariances of both worlds! homogeneous and isotropic structure of horizontal analysis increments (for CV), that have a bad power spectrum (Gaussian assumption) homogeneous structure of vertical correlation (for CV) homogeneous σ b (they are the sqrt of EOF eigenvalues) Moreover, the horizontal analysis increments looks not so good (c.f. PSOT results of gen_be_stage4_regional without tuning of lengthscales). Yann MICHEL B modelling: climatological flow-dependence 3

4 A new estimate of lengthscales The Wu, Purser and Parrish (2002) formula The correlation lengthscale can be estimated through the ration of the variance of the field to the variance of its Laplacian: L = 8 V «1/4 ψ V ζ gen_be_stage4_regional_from_variances * for each member (date or ensemble) + for each vertical level or EOF mode - perform spatial laplacian computation with fft - accumulate variance for projected field - accumulate variance for projected Laplacian field + end * end * Compute lengthscales Yann MICHEL B modelling: climatological flow-dependence 5

5 A new estimate of lengthscales: results for CONUS 200 We obtain local lengthscales which noise seems in agreement with Pannekoucke et al (2008) and choose to use the median over the domain. Figure: Comparison of raw lengthscales obtained over the CONUS domain (200 km resolution) for the fit of spatial correlation (gen_be_stage4_regional) and the new estimate from the variances (gen_be_stage4_regional_from_variances) Yann MICHEL B modelling: climatological flow-dependence 6

6 A new estimate of lengthscales: results for AMPSRT 45 Comparison Smoother results over the EOF mode (more robust). Shorter lengthscales for ψ, χ u and larger for t u, rh. Figure: Same comparison over the AMPSRT domain (45 km resolution) Yann MICHEL B modelling: climatological flow-dependence 7

7 Single observation experiments (PSOT) Figure: PSOT over the AMPSRT domain (45 km resolution) for a u observation Yann MICHEL B modelling: climatological flow-dependence 8

8 Single observation experiments (PSOT) Figure: PSOT over the AMPSRT domain (45 km resolution) for a u observation Yann MICHEL B modelling: climatological flow-dependence 8

9 Single observation experiments (PSOT) Figure: PSOT over the AMPSRT domain (45 km resolution) for a t observation Yann MICHEL B modelling: climatological flow-dependence 9

10 Single observation experiments (PSOT) Figure: PSOT over the AMPSRT domain (45 km resolution) for a t observation Yann MICHEL B modelling: climatological flow-dependence 9

11 Single observation experiments (PSOT) Figure: PSOT over the AMPSRT domain (45 km resolution) for a rh observation Yann MICHEL B modelling: climatological flow-dependence 10

12 Modelling the climatological flow-dependence Currently, the bin_type in gen_be is an on-off way of specifying B. It allows j-dependence of Regression coefficients (stage 2, U p ) Eigenvalues/vectors of vertical covariance (stage 3, U v ) Lengthscales (stage 4, U h ) But when the grid is not j/latitude (as for AMPSRT), we are restricted to homogeneity (bin_type 5) x = U p U v U h v (1) Yann MICHEL B modelling: climatological flow-dependence 11

13 Varying background error variances gen_be_stage4_regional_from_variances provides gridpoint variances of fields on EOF modes that could be used to add climatological dependence of background error variances. Figure: Variance for ψ and χ u on EOF 1 Yann MICHEL B modelling: climatological flow-dependence 12

14 Varying background error lengthscales gen_be_stage4_regional_from_variances provides gridpoint lengthscales of fields on EOF modes Figure: Lengthscale for ψ and χu on EOF 1 Yann MICHEL B modelling: climatological flow-dependence 13

15 Varying background error lengthscales: recursive filters Recursive filters can deal with smoothly varying lengthscales, but the amplitude of the filter has to be reconsidered (Purser et.al, 2003). Basic equation of recursive filter of smoothing parameter α can easily be made grid-dependent. A i = αa i 1 + (1 α)a i Figure: A varying lengthscale (km) Impulse Figure: Impulse response of the 6-order recursive filter. Yann MICHEL B modelling: climatological flow-dependence 14

16 Varying background error lengthscales in WRFVAR An academic test where the background error lengthscales are increasing by a factor of 2 from West to East. Still some work to go to achieve proper normalization of the amplitude of the recursive filters. Yann MICHEL B modelling: climatological flow-dependence 15

17 Conclusion Climatological flow-dependence New way of computing lengthscales, more efficient, looks better. On the way of specifying varying background error variances On the way of specifying varying background error lengthscales With bin_type=0, one can have varying regression coefficients (not shown) Filtering Variances, Lengthscales and Regression coefficients may need to be locally averaged (spatially and or temporally averaged). The filter could be adaptive to the noise level and structure (Berre, Raynaud, Pannekoucke). Flow-dependence of the day This improvements could be used with the hybrid framework, but still a lot of work before. Yann MICHEL B modelling: climatological flow-dependence 16

Inhomogeneous Background Error Modeling and Estimation over Antarctica with WRF-Var/AMPS

Inhomogeneous Background Error Modeling and Estimation over Antarctica with WRF-Var/AMPS Inhomogeneous Background Error Modeling and Estimation over Antarctica with WRF-Var/AMPS Yann MICHEL 1 Météo-France, CNRM/GMAP 2 NCAR, MMM/DAG 10 th Annual WRF Users Workshop 23 th June 2009 Yann MICHEL

More information

The ECMWF Hybrid 4D-Var and Ensemble of Data Assimilations

The ECMWF Hybrid 4D-Var and Ensemble of Data Assimilations The Hybrid 4D-Var and Ensemble of Data Assimilations Lars Isaksen, Massimo Bonavita and Elias Holm Data Assimilation Section lars.isaksen@ecmwf.int Acknowledgements to: Mike Fisher and Marta Janiskova

More information

GSI Tutorial Background and Observation Error Estimation and Tuning. 8/6/2013 Wan-Shu Wu 1

GSI Tutorial Background and Observation Error Estimation and Tuning. 8/6/2013 Wan-Shu Wu 1 GSI Tutorial 2013 Background and Observation Error Estimation and Tuning 8/6/2013 Wan-Shu Wu 1 Analysis system produces an analysis through the minimization of an objective function given by J = x T B

More information

Filtering of variances and correlations by local spatial averaging. Loïk Berre Météo-France

Filtering of variances and correlations by local spatial averaging. Loïk Berre Météo-France Filtering of variances and correlations by local spatial averaging Loïk Berre Météo-France Outline 1. Contrast between two extreme approaches in Var/EnKF? 2.The spatial structure of sampling noise and

More information

Background Error Covariance Modelling

Background Error Covariance Modelling Background Error Covariance Modelling Mike Fisher Slide 1 Outline Diagnosing the Statistics of Background Error using Ensembles of Analyses Modelling the Statistics in Spectral Space - Relaxing constraints

More information

Comparison of 3D-Var and LETKF in an Atmospheric GCM: SPEEDY

Comparison of 3D-Var and LETKF in an Atmospheric GCM: SPEEDY Comparison of 3D-Var and LEKF in an Atmospheric GCM: SPEEDY Catherine Sabol Kayo Ide Eugenia Kalnay, akemasa Miyoshi Weather Chaos, UMD 9 April 2012 Outline SPEEDY Formulation Single Observation Eperiments

More information

13A. 4 Analysis and Impact of Super-obbed Doppler Radial Velocity in the NCEP Grid-point Statistical Interpolation (GSI) Analysis System

13A. 4 Analysis and Impact of Super-obbed Doppler Radial Velocity in the NCEP Grid-point Statistical Interpolation (GSI) Analysis System 13A. 4 Analysis and Impact of Super-obbed Doppler Radial Velocity in the NCEP Grid-point Statistical Interpolation (GSI) Analysis System Shun Liu 1, Ming Xue 1,2, Jidong Gao 1,2 and David Parrish 3 1 Center

More information

GSI Tutorial Background and Observation Errors: Estimation and Tuning. Daryl Kleist NCEP/EMC June 2011 GSI Tutorial

GSI Tutorial Background and Observation Errors: Estimation and Tuning. Daryl Kleist NCEP/EMC June 2011 GSI Tutorial GSI Tutorial 2011 Background and Observation Errors: Estimation and Tuning Daryl Kleist NCEP/EMC 29-30 June 2011 GSI Tutorial 1 Background Errors 1. Background error covariance 2. Multivariate relationships

More information

An Ensemble Kalman Filter for NWP based on Variational Data Assimilation: VarEnKF

An Ensemble Kalman Filter for NWP based on Variational Data Assimilation: VarEnKF An Ensemble Kalman Filter for NWP based on Variational Data Assimilation: VarEnKF Blueprints for Next-Generation Data Assimilation Systems Workshop 8-10 March 2016 Mark Buehner Data Assimilation and Satellite

More information

Representation of inhomogeneous, non-separable covariances by sparse wavelet-transformed matrices

Representation of inhomogeneous, non-separable covariances by sparse wavelet-transformed matrices Representation of inhomogeneous, non-separable covariances by sparse wavelet-transformed matrices Andreas Rhodin, Harald Anlauf German Weather Service (DWD) Workshop on Flow-dependent aspects of data assimilation,

More information

Signal Modeling Techniques in Speech Recognition. Hassan A. Kingravi

Signal Modeling Techniques in Speech Recognition. Hassan A. Kingravi Signal Modeling Techniques in Speech Recognition Hassan A. Kingravi Outline Introduction Spectral Shaping Spectral Analysis Parameter Transforms Statistical Modeling Discussion Conclusions 1: Introduction

More information

Assimilation of cloud/precipitation data at regional scales

Assimilation of cloud/precipitation data at regional scales Assimilation of cloud/precipitation data at regional scales Thomas Auligné National Center for Atmospheric Research auligne@ucar.edu Acknowledgments to: Steven Cavallo, David Dowell, Aimé Fournier, Hans

More information

Time Series: Theory and Methods

Time Series: Theory and Methods Peter J. Brockwell Richard A. Davis Time Series: Theory and Methods Second Edition With 124 Illustrations Springer Contents Preface to the Second Edition Preface to the First Edition vn ix CHAPTER 1 Stationary

More information

Hilbert Space Methods for Reduced-Rank Gaussian Process Regression

Hilbert Space Methods for Reduced-Rank Gaussian Process Regression Hilbert Space Methods for Reduced-Rank Gaussian Process Regression Arno Solin and Simo Särkkä Aalto University, Finland Workshop on Gaussian Process Approximation Copenhagen, Denmark, May 2015 Solin &

More information

Data Assimilation Research Testbed Tutorial

Data Assimilation Research Testbed Tutorial Data Assimilation Research Testbed Tutorial Section 3: Hierarchical Group Filters and Localization Version 2.: September, 26 Anderson: Ensemble Tutorial 9//6 Ways to deal with regression sampling error:

More information

Multivariate Correlations: Applying a Dynamic Constraint and Variable Localization in an Ensemble Context

Multivariate Correlations: Applying a Dynamic Constraint and Variable Localization in an Ensemble Context Multivariate Correlations: Applying a Dynamic Constraint and Variable Localization in an Ensemble Context Catherine Thomas 1,2,3, Kayo Ide 1 Additional thanks to Daryl Kleist, Eugenia Kalnay, Takemasa

More information

DATA ASSIMILATION FOR FLOOD FORECASTING

DATA ASSIMILATION FOR FLOOD FORECASTING DATA ASSIMILATION FOR FLOOD FORECASTING Arnold Heemin Delft University of Technology 09/16/14 1 Data assimilation is the incorporation of measurement into a numerical model to improve the model results

More information

Numerical Weather prediction at the European Centre for Medium-Range Weather Forecasts (2)

Numerical Weather prediction at the European Centre for Medium-Range Weather Forecasts (2) Numerical Weather prediction at the European Centre for Medium-Range Weather Forecasts (2) Time series curves 500hPa geopotential Correlation coefficent of forecast anomaly N Hemisphere Lat 20.0 to 90.0

More information

Objective localization of ensemble covariances: theory and applications

Objective localization of ensemble covariances: theory and applications Institutionnel Grand Public Objective localization of ensemble covariances: theory and applications Yann Michel1, B. Me ne trier2 and T. Montmerle1 Professionnel (1) Me te o-france & CNRS, Toulouse, France

More information

Simulation of error cycling

Simulation of error cycling Simulation of error cycling Loïk BERRE, Météo-France/CNRS ISDA, Reading, 21 July 2016 with inputs from R. El Ouaraini, L. Raynaud, G. Desroziers, C. Fischer Motivations and questions EDA and innovations

More information

The hybrid ETKF- Variational data assimilation scheme in HIRLAM

The hybrid ETKF- Variational data assimilation scheme in HIRLAM The hybrid ETKF- Variational data assimilation scheme in HIRLAM (current status, problems and further developments) The Hungarian Meteorological Service, Budapest, 24.01.2011 Nils Gustafsson, Jelena Bojarova

More information

Can hybrid-4denvar match hybrid-4dvar?

Can hybrid-4denvar match hybrid-4dvar? Comparing ensemble-variational assimilation methods for NWP: Can hybrid-4denvar match hybrid-4dvar? WWOSC, Montreal, August 2014. Andrew Lorenc, Neill Bowler, Adam Clayton, David Fairbairn and Stephen

More information

Spectral and morphing ensemble Kalman filters

Spectral and morphing ensemble Kalman filters Spectral and morphing ensemble Kalman filters Department of Mathematical and Statistical Sciences University of Colorado Denver 91st American Meteorological Society Annual Meeting Seattle, WA, January

More information

The Impact of Background Error Statistics and MODIS Winds for AMPS

The Impact of Background Error Statistics and MODIS Winds for AMPS The Impact of Background Error Statistics and MODIS Winds for AMPS Syed RH Rizvi, Dale M. Barker, Jordan G. Powers and Michael G. Duda National Center For Atmospheric Research NCAR/MMM, Bolder, CO-80307,

More information

T2.3: Use of ensemble information in ocean analysis and development of efficient 4D-Var

T2.3: Use of ensemble information in ocean analysis and development of efficient 4D-Var T2.3: Use of ensemble information in ocean analysis and development of efficient 4D-Var A. Weaver 1,B.Ménétrier 1,J.Tshimanga 1 and A. Vidard 2 1 CERFACS, Toulouse 2 INRIA/LJK, Grenoble December 10, 2015

More information

Recent Developments in Numerical Methods for 4d-Var

Recent Developments in Numerical Methods for 4d-Var Recent Developments in Numerical Methods for 4d-Var Mike Fisher Slide 1 Recent Developments Numerical Methods 4d-Var Slide 2 Outline Non-orthogonal wavelets on the sphere: - Motivation: Covariance Modelling

More information

Reducing the Impact of Sampling Errors in Ensemble Filters

Reducing the Impact of Sampling Errors in Ensemble Filters Reducing the Impact of Sampling Errors in Ensemble Filters Jeffrey Anderson NCAR Data Assimilation Research Section The National Center for Atmospheric Research is sponsored by the National Science Foundation.

More information

4DEnVar. Four-Dimensional Ensemble-Variational Data Assimilation. Colloque National sur l'assimilation de données

4DEnVar. Four-Dimensional Ensemble-Variational Data Assimilation. Colloque National sur l'assimilation de données Four-Dimensional Ensemble-Variational Data Assimilation 4DEnVar Colloque National sur l'assimilation de données Andrew Lorenc, Toulouse France. 1-3 décembre 2014 Crown copyright Met Office 4DEnVar: Topics

More information

Met Office convective-scale 4DVAR system, tests and improvement

Met Office convective-scale 4DVAR system, tests and improvement Met Office convective-scale 4DVAR system, tests and improvement Marco Milan*, Marek Wlasak, Stefano Migliorini, Bruce Macpherson Acknowledgment: Inverarity Gordon, Gareth Dow, Mike Thurlow, Mike Cullen

More information

Loïk Berre Météo-France (CNRM/GAME) Thanks to Gérald Desroziers

Loïk Berre Météo-France (CNRM/GAME) Thanks to Gérald Desroziers Estimation and diagnosis of analysis/background errors using ensemble assimilation Loïk Berre Météo-France (CNRM/GAME) Thanks to Gérald Desroziers Outline 1. Simulation of the error evolution 2. The operational

More information

Review of Covariance Localization in Ensemble Filters

Review of Covariance Localization in Ensemble Filters NOAA Earth System Research Laboratory Review of Covariance Localization in Ensemble Filters Tom Hamill NOAA Earth System Research Lab, Boulder, CO tom.hamill@noaa.gov Canonical ensemble Kalman filter update

More information

Variational ensemble DA at Météo-France Cliquez pour modifier le style des sous-titres du masque

Variational ensemble DA at Météo-France Cliquez pour modifier le style des sous-titres du masque Cliquez pour modifier le style du titre Variational ensemble DA at Météo-France Cliquez pour modifier le style des sous-titres du masque L. Berre, G. Desroziers, H. Varella, L. Raynaud, C. Labadie and

More information

Background Error, Observation Error, and GSI Hybrid Analysis

Background Error, Observation Error, and GSI Hybrid Analysis 2015 GSI Community Tutorial August 11-13, 2013, NCAR, Boulder Background Error, Observation Error, and GSI Hybrid Analysis Ming Hu Developmental Testbed Center Outlines GSI fundamentals (1): Setup and

More information

Modelling of background error covariances for the analysis of clouds and precipitation

Modelling of background error covariances for the analysis of clouds and precipitation Modelling of background error covariances for the analysis of clouds and precipitation Thibaut Montmerle, Yann Michel and Benjamin Ménétrier Météo-France/CNRM-GAME 42 av. G. Coriolis, 31057 Toulouse, France

More information

Empirical Mean and Variance!

Empirical Mean and Variance! Global Image Properties! Global image properties refer to an image as a whole rather than components. Computation of global image properties is often required for image enhancement, preceding image analysis.!

More information

The Use of a Self-Evolving Additive Inflation in the CNMCA Ensemble Data Assimilation System

The Use of a Self-Evolving Additive Inflation in the CNMCA Ensemble Data Assimilation System The Use of a Self-Evolving Additive Inflation in the CNMCA Ensemble Data Assimilation System Lucio Torrisi and Francesca Marcucci CNMCA, Italian National Met Center Outline Implementation of the LETKF

More information

ECE Digital Image Processing and Introduction to Computer Vision. Outline

ECE Digital Image Processing and Introduction to Computer Vision. Outline 2/9/7 ECE592-064 Digital Image Processing and Introduction to Computer Vision Depart. of ECE, NC State University Instructor: Tianfu (Matt) Wu Spring 207. Recap Outline 2. Sharpening Filtering Illustration

More information

552 Final Exam Preparation: 3/12/14 9:39 AM Page 1 of 7

552 Final Exam Preparation: 3/12/14 9:39 AM Page 1 of 7 55 Final Exam Preparation: 3/1/1 9:39 AM Page 1 of 7 ATMS 55: Objective Analysis Final Preparation 1. A variable y that you wish to predict is correlated with x at.7, and with z at.. The two predictors

More information

Heterogeneous Convective-Scale Background Error Covariances with the Inclusion of Hydrometeor Variables

Heterogeneous Convective-Scale Background Error Covariances with the Inclusion of Hydrometeor Variables 2994 M O N T H L Y W E A T H E R R E V I E W VOLUME 139 Heterogeneous Convective-Scale Background Error Covariances with the Inclusion of Hydrometeor Variables YANN MICHEL Météo-France, CNRM-GAME and CNRS,

More information

Brian J. Etherton University of North Carolina

Brian J. Etherton University of North Carolina Brian J. Etherton University of North Carolina The next 90 minutes of your life Data Assimilation Introit Different methodologies Barnes Analysis in IDV NWP Error Sources 1. Intrinsic Predictability Limitations

More information

A general hybrid formulation of the background-error covariance matrix for ensemble-variational ocean data assimilation

A general hybrid formulation of the background-error covariance matrix for ensemble-variational ocean data assimilation .. A general hybrid formulation of the background-error covariance matrix for ensemble-variational ocean data assimilation Anthony Weaver Andrea Piacentini, Serge Gratton, Selime Gürol, Jean Tshimanga

More information

Hybrid variational-ensemble data assimilation. Daryl T. Kleist. Kayo Ide, Dave Parrish, John Derber, Jeff Whitaker

Hybrid variational-ensemble data assimilation. Daryl T. Kleist. Kayo Ide, Dave Parrish, John Derber, Jeff Whitaker Hybrid variational-ensemble data assimilation Daryl T. Kleist Kayo Ide, Dave Parrish, John Derber, Jeff Whitaker Weather and Chaos Group Meeting 07 March 20 Variational Data Assimilation J Var J 2 2 T

More information

Problems with EOF (unrotated)

Problems with EOF (unrotated) Rotated EOFs: When the domain sizes are larger than optimal for conventional EOF analysis but still small enough so that the real structure in the data is not completely obscured by sampling variability,

More information

Introduction. Spatial Processes & Spatial Patterns

Introduction. Spatial Processes & Spatial Patterns Introduction Spatial data: set of geo-referenced attribute measurements: each measurement is associated with a location (point) or an entity (area/region/object) in geographical (or other) space; the domain

More information

Spectral and morphing ensemble Kalman filters

Spectral and morphing ensemble Kalman filters Spectral and morphing ensemble Kalman filters Department of Mathematical and Statistical Sciences University of Colorado Denver 91st American Meteorological Society Annual Meeting Seattle, WA, January

More information

USE OF SURFACE MESONET DATA IN THE NCEP REGIONAL GSI SYSTEM

USE OF SURFACE MESONET DATA IN THE NCEP REGIONAL GSI SYSTEM 6A.7 USE OF SURFACE MESONET DATA IN THE NCEP REGIONAL GSI SYSTEM Seung-Jae Lee *, David F. Parrish, Wan-Shu Wu, Manuel Pondeca, Dennis Keyser, and Geoffery J. DiMego NCEP/Environmental Meteorological Center,

More information

15B.7 A SEQUENTIAL VARIATIONAL ANALYSIS APPROACH FOR MESOSCALE DATA ASSIMILATION

15B.7 A SEQUENTIAL VARIATIONAL ANALYSIS APPROACH FOR MESOSCALE DATA ASSIMILATION 21st Conference on Weather Analysis and Forecasting/17th Conference on Numerical Weather Prediction 15B.7 A SEQUENTIAL VARIATIONAL ANALYSIS APPROACH FOR MESOSCALE DATA ASSIMILATION Yuanfu Xie 1, S. E.

More information

A Comparison between the 3/4DVAR and Hybrid Ensemble-VAR Techniques for Radar Data Assimilation ABSTRACT

A Comparison between the 3/4DVAR and Hybrid Ensemble-VAR Techniques for Radar Data Assimilation ABSTRACT 36 th AMS CONFERENCE ON RADAR METEOROLOGY, 16-2 SEPTEMBER 213, BRECKENRIDGE, COLORADO A Comparison between the 3/4DVAR and Hybrid Ensemble-VAR Techniques for Radar Data Assimilation Hongli Wang *1, Xiang-Yu

More information

Adaptive Localization: Proposals for a high-resolution multivariate system Ross Bannister, HRAA, December 2008, January 2009 Version 3.

Adaptive Localization: Proposals for a high-resolution multivariate system Ross Bannister, HRAA, December 2008, January 2009 Version 3. Adaptive Localization: Proposals for a high-resolution multivariate system Ross Bannister, HRAA, December 2008, January 2009 Version 3.. The implicit Schur product 2. The Bishop method for adaptive localization

More information

A computationally efficient approach to generate large ensembles of coherent climate data for GCAM

A computationally efficient approach to generate large ensembles of coherent climate data for GCAM A computationally efficient approach to generate large ensembles of coherent climate data for GCAM GCAM Community Modeling Meeting Joint Global Change Research Institute, College Park MD November 7 th,

More information

Cross-validation methods for quality control, cloud screening, etc.

Cross-validation methods for quality control, cloud screening, etc. Cross-validation methods for quality control, cloud screening, etc. Olaf Stiller, Deutscher Wetterdienst Are observations consistent Sensitivity functions with the other observations? given the background

More information

New data analysis for AURIGA. Lucio Baggio Italy, INFN and University of Trento AURIGA

New data analysis for AURIGA. Lucio Baggio Italy, INFN and University of Trento AURIGA New data analysis for AURIGA Lucio Baggio Italy, INFN and University of Trento AURIGA The (new) AURIGA data analysis Since 2001 the AURIGA data analysis for burst search have been rewritten from scratch

More information

Alexander Barth, Aida Alvera-Azc. Azcárate, Robert H. Weisberg, University of South Florida. George Halliwell RSMAS, University of Miami

Alexander Barth, Aida Alvera-Azc. Azcárate, Robert H. Weisberg, University of South Florida. George Halliwell RSMAS, University of Miami Ensemble-based based Assimilation of HF-Radar Surface Currents in a West Florida Shelf ROMS Nested into HYCOM and filtering of spurious surface gravity waves. Alexander Barth, Aida Alvera-Azc Azcárate,

More information

Statistics 910, #15 1. Kalman Filter

Statistics 910, #15 1. Kalman Filter Statistics 910, #15 1 Overview 1. Summary of Kalman filter 2. Derivations 3. ARMA likelihoods 4. Recursions for the variance Kalman Filter Summary of Kalman filter Simplifications To make the derivations

More information

Simple Examples. Let s look at a few simple examples of OI analysis.

Simple Examples. Let s look at a few simple examples of OI analysis. Simple Examples Let s look at a few simple examples of OI analysis. Example 1: Consider a scalar prolem. We have one oservation y which is located at the analysis point. We also have a ackground estimate

More information

Covariance Localization with the Diffusion-Based Correlation Models

Covariance Localization with the Diffusion-Based Correlation Models 848 M O N T H L Y W E A T H E R R E V I E W VOLUME 141 Covariance Localization with the Diffusion-Based Correlation Models MAX YAREMCHUK Naval Research Laboratory, Stennis Space Center, Mississippi DMITRY

More information

Relationship between Singular Vectors, Bred Vectors, 4D-Var and EnKF

Relationship between Singular Vectors, Bred Vectors, 4D-Var and EnKF Relationship between Singular Vectors, Bred Vectors, 4D-Var and EnKF Eugenia Kalnay and Shu-Chih Yang with Alberto Carrasi, Matteo Corazza and Takemasa Miyoshi 4th EnKF Workshop, April 2010 Relationship

More information

Progress in developing a 3D background error correlation model using an implicit diusion operator

Progress in developing a 3D background error correlation model using an implicit diusion operator Progress in developing a 3D background error correlation model using an implicit diusion operator Isabelle Mirouze 1 et Anthony T. Weaver 2 1 CERFACS / CNRS-UMR 5219 2 CERFACS / SUC URA 1875 VODA: intermediary

More information

A HYBRID ENSEMBLE KALMAN FILTER / 3D-VARIATIONAL ANALYSIS SCHEME

A HYBRID ENSEMBLE KALMAN FILTER / 3D-VARIATIONAL ANALYSIS SCHEME A HYBRID ENSEMBLE KALMAN FILTER / 3D-VARIATIONAL ANALYSIS SCHEME Thomas M. Hamill and Chris Snyder National Center for Atmospheric Research, Boulder, Colorado 1. INTRODUCTION Given the chaotic nature of

More information

Recent developments for CNMCA LETKF

Recent developments for CNMCA LETKF Recent developments for CNMCA LETKF Lucio Torrisi and Francesca Marcucci CNMCA, Italian National Met Center Outline Implementation of the LETKF at CNMCA Treatment of model error in the CNMCA-LETKF The

More information

(Regional) Climate Model Validation

(Regional) Climate Model Validation (Regional) Climate Model Validation Francis W. Zwiers Canadian Centre for Climate Modelling and Analysis Atmospheric Environment Service Victoria, BC Outline - three questions What sophisticated validation

More information

Introduction to GSI Background Error Covariance (BE)

Introduction to GSI Background Error Covariance (BE) 23 Beijing GSI Tutorial May 29, 23 Beijing, China Introduction to GSI Background Error Covariance (BE) Ming Hu Developmental Testbed Center NCAR-NOAA/GSD BE related Tutorial lectures GSI Tutorial 2 Background

More information

Estimation of the local diffusion tensor and normalization for heterogeneous correlation modelling using a diffusion equation

Estimation of the local diffusion tensor and normalization for heterogeneous correlation modelling using a diffusion equation QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY Q. J. R. Meteorol. Soc. 134: 1425 1438 (2008) Published online 12 August 2008 in Wiley InterScience (www.interscience.wiley.com).288 Estimation of

More information

Filtering and Edge Detection

Filtering and Edge Detection Filtering and Edge Detection Local Neighborhoods Hard to tell anything from a single pixel Example: you see a reddish pixel. Is this the object s color? Illumination? Noise? The next step in order of complexity

More information

Report on the Joint SRNWP workshop on DA-EPS Bologna, March. Nils Gustafsson Alex Deckmyn.

Report on the Joint SRNWP workshop on DA-EPS Bologna, March. Nils Gustafsson Alex Deckmyn. Report on the Joint SRNWP workshop on DA-EPS Bologna, 22-24 March Nils Gustafsson Alex Deckmyn http://www.smr.arpa.emr.it/srnwp/ Purpose of the workshop On the one hand, data assimilation techniques require

More information

Image Noise: Detection, Measurement and Removal Techniques. Zhifei Zhang

Image Noise: Detection, Measurement and Removal Techniques. Zhifei Zhang Image Noise: Detection, Measurement and Removal Techniques Zhifei Zhang Outline Noise measurement Filter-based Block-based Wavelet-based Noise removal Spatial domain Transform domain Non-local methods

More information

Retrieval of Moisture from Simulated GPS Slant-Path Water Vapor Observations Using 3DVAR with Anisotropic Recursive Filters

Retrieval of Moisture from Simulated GPS Slant-Path Water Vapor Observations Using 3DVAR with Anisotropic Recursive Filters 1506 M O N T H L Y W E A T H E R R E V I E W VOLUME 135 Retrieval of Moisture from Simulated GPS Slant-Path Water Vapor Observations Using 3DVAR with Anisotropic Recursive Filters HAIXIA LIU AND MING XUE

More information

Background Error Covariance! and GEN_BE!!! Tom Auligné! Gael Descombes!!!!!!

Background Error Covariance! and GEN_BE!!! Tom Auligné! Gael Descombes!!!!!! 2014 GSI Community Tutorial Background Error Covariance and GEN_BE Tom Auligné Gael Descombes Acknowledgments: R. Bannister, D. Barker, S. Rizvi, W-S. Wu Partial funding provided by the Air Force Weather

More information

Comparing the SEKF with the DEnKF on a land surface model

Comparing the SEKF with the DEnKF on a land surface model Comparing the SEKF with the DEnKF on a land surface model David Fairbairn, Alina Barbu, Emiliano Gelati, Jean-Francois Mahfouf and Jean-Christophe Caret CNRM - Meteo France Partly funded by European Union

More information

We will of course continue using the discrete form of the power spectrum described via calculation of α and β.

We will of course continue using the discrete form of the power spectrum described via calculation of α and β. The present lecture is the final lecture on the analysis of the power spectrum. The coming lectures will deal with correlation analysis of non sinusoidal signals. We will of course continue using the discrete

More information

The Canadian approach to ensemble prediction

The Canadian approach to ensemble prediction The Canadian approach to ensemble prediction ECMWF 2017 Annual seminar: Ensemble prediction : past, present and future. Pieter Houtekamer Montreal, Canada Overview. The Canadian approach. What are the

More information

MACHINE LEARNING. Methods for feature extraction and reduction of dimensionality: Probabilistic PCA and kernel PCA

MACHINE LEARNING. Methods for feature extraction and reduction of dimensionality: Probabilistic PCA and kernel PCA 1 MACHINE LEARNING Methods for feature extraction and reduction of dimensionality: Probabilistic PCA and kernel PCA 2 Practicals Next Week Next Week, Practical Session on Computer Takes Place in Room GR

More information

How 4DVAR can benefit from or contribute to EnKF (a 4DVAR perspective)

How 4DVAR can benefit from or contribute to EnKF (a 4DVAR perspective) How 4DVAR can benefit from or contribute to EnKF (a 4DVAR perspective) Dale Barker WWRP/THORPEX Workshop on 4D-Var and Ensemble Kalman Filter Intercomparisons Sociedad Cientifica Argentina, Buenos Aires,

More information

Recent achievements in the data assimilation systems of ARPEGE and AROME-France

Recent achievements in the data assimilation systems of ARPEGE and AROME-France Recent achievements in the data assimilation systems of ARPEGE and AROME-France P. Brousseau and many colleagues from (CNRM/GMAP) 38th EWGLAM and 23 SRNWP Meeting Rome, 04 October 2016 Meteo-France NWP

More information

SIO 210 CSP: Data analysis methods L. Talley, Fall Sampling and error 2. Basic statistical concepts 3. Time series analysis

SIO 210 CSP: Data analysis methods L. Talley, Fall Sampling and error 2. Basic statistical concepts 3. Time series analysis SIO 210 CSP: Data analysis methods L. Talley, Fall 2016 1. Sampling and error 2. Basic statistical concepts 3. Time series analysis 4. Mapping 5. Filtering 6. Space-time data 7. Water mass analysis Reading:

More information

Standardized Anomaly Model Output Statistics Over Complex Terrain.

Standardized Anomaly Model Output Statistics Over Complex Terrain. Standardized Anomaly Model Output Statistics Over Complex Terrain Reto.Stauffer@uibk.ac.at Outline statistical ensemble postprocessing introduction to SAMOS new snow amount forecasts in Tyrol sub-seasonal

More information

Image Filtering. Slides, adapted from. Steve Seitz and Rick Szeliski, U.Washington

Image Filtering. Slides, adapted from. Steve Seitz and Rick Szeliski, U.Washington Image Filtering Slides, adapted from Steve Seitz and Rick Szeliski, U.Washington The power of blur All is Vanity by Charles Allen Gillbert (1873-1929) Harmon LD & JuleszB (1973) The recognition of faces.

More information

The Ensemble Kalman Filter:

The Ensemble Kalman Filter: p.1 The Ensemble Kalman Filter: Theoretical formulation and practical implementation Geir Evensen Norsk Hydro Research Centre, Bergen, Norway Based on Evensen, Ocean Dynamics, Vol 5, No p. The Ensemble

More information

Spatial smoothing using Gaussian processes

Spatial smoothing using Gaussian processes Spatial smoothing using Gaussian processes Chris Paciorek paciorek@hsph.harvard.edu August 5, 2004 1 OUTLINE Spatial smoothing and Gaussian processes Covariance modelling Nonstationary covariance modelling

More information

Model Selection for Gaussian Processes

Model Selection for Gaussian Processes Institute for Adaptive and Neural Computation School of Informatics,, UK December 26 Outline GP basics Model selection: covariance functions and parameterizations Criteria for model selection Marginal

More information

Satellite Retrieval Assimilation (a modified observation operator)

Satellite Retrieval Assimilation (a modified observation operator) Satellite Retrieval Assimilation (a modified observation operator) David D. Kuhl With Istvan Szunyogh and Brad Pierce Sept. 21 2009 Weather Chaos Group Meeting Overview Introduction Derivation of retrieval

More information

Sensor Tasking and Control

Sensor Tasking and Control Sensor Tasking and Control Sensing Networking Leonidas Guibas Stanford University Computation CS428 Sensor systems are about sensing, after all... System State Continuous and Discrete Variables The quantities

More information

The Impact of Background Error on Incomplete Observations for 4D-Var Data Assimilation with the FSU GSM

The Impact of Background Error on Incomplete Observations for 4D-Var Data Assimilation with the FSU GSM The Impact of Background Error on Incomplete Observations for 4D-Var Data Assimilation with the FSU GSM I. Michael Navon 1, Dacian N. Daescu 2, and Zhuo Liu 1 1 School of Computational Science and Information

More information

Comparing two different methods to describe radar precipitation uncertainty

Comparing two different methods to describe radar precipitation uncertainty Comparing two different methods to describe radar precipitation uncertainty Francesca Cecinati, Miguel A. Rico-Ramirez, Dawei Han, University of Bristol, Department of Civil Engineering Corresponding author:

More information

Anisotropic spatial filter that is based on flow-dependent background error structures is implemented and tested.

Anisotropic spatial filter that is based on flow-dependent background error structures is implemented and tested. Special Topics 3DVAR Analysis/Retrieval of 3D water vapor from GPS slant water data Liu, H. and M. Xue, 2004: 3DVAR retrieval of 3D moisture field from slant-path water vapor observations of a high-resolution

More information

Basics on 2-D 2 D Random Signal

Basics on 2-D 2 D Random Signal Basics on -D D Random Signal Spring 06 Instructor: K. J. Ray Liu ECE Department, Univ. of Maryland, College Park Overview Last Time: Fourier Analysis for -D signals Image enhancement via spatial filtering

More information

Direct Learning: Linear Classification. Donglin Zeng, Department of Biostatistics, University of North Carolina

Direct Learning: Linear Classification. Donglin Zeng, Department of Biostatistics, University of North Carolina Direct Learning: Linear Classification Logistic regression models for classification problem We consider two class problem: Y {0, 1}. The Bayes rule for the classification is I(P(Y = 1 X = x) > 1/2) so

More information

Templates, Image Pyramids, and Filter Banks

Templates, Image Pyramids, and Filter Banks Templates, Image Pyramids, and Filter Banks 09/9/ Computer Vision James Hays, Brown Slides: Hoiem and others Review. Match the spatial domain image to the Fourier magnitude image 2 3 4 5 B A C D E Slide:

More information

How does 4D-Var handle Nonlinearity and non-gaussianity?

How does 4D-Var handle Nonlinearity and non-gaussianity? How does 4D-Var handle Nonlinearity and non-gaussianity? Mike Fisher Acknowledgements: Christina Tavolato, Elias Holm, Lars Isaksen, Tavolato, Yannick Tremolet Slide 1 Outline of Talk Non-Gaussian pdf

More information

Lifting Detail from Darkness

Lifting Detail from Darkness Lifting Detail from Darkness J.P.Lewis zilla@computer.org Disney The Secret Lab Lewis / Detail from Darkness p.1/38 Brightness-Detail Decomposition detail image image intensity Separate detail by Wiener

More information

A Hybrid ETKF 3DVAR Data Assimilation Scheme for the WRF Model. Part I: Observing System Simulation Experiment

A Hybrid ETKF 3DVAR Data Assimilation Scheme for the WRF Model. Part I: Observing System Simulation Experiment 5116 M O N T H L Y W E A T H E R R E V I E W VOLUME 136 A Hybrid ETKF 3DVAR Data Assimilation Scheme for the WRF Model. Part I: Observing System Simulation Experiment XUGUANG WANG Cooperative Institute

More information

Developments to the assimilation of sea surface temperature

Developments to the assimilation of sea surface temperature Developments to the assimilation of sea surface temperature James While, Daniel Lea, Matthew Martin ERA-CLIM2 General Assembly, January 2017 Contents Introduction Improvements to SST bias correction Development

More information

AMS 17th Conference on Numerical Weather Predition, 1-5 August 2005, Washington D.C. Paper 16A.3

AMS 17th Conference on Numerical Weather Predition, 1-5 August 2005, Washington D.C. Paper 16A.3 AMS 17th Conference on Numerical Weather Predition, 1-5 August 2005, Washington D.C. Paper 16A.3 HIGH-RESOLUTION WINTER-SEASON NWP: PRELIMINARY EVALUATION OF THE WRF ARW AND NMM MODELS IN THE DWFE FORECAST

More information

Learning gradients: prescriptive models

Learning gradients: prescriptive models Department of Statistical Science Institute for Genome Sciences & Policy Department of Computer Science Duke University May 11, 2007 Relevant papers Learning Coordinate Covariances via Gradients. Sayan

More information

Feb 21 and 25: Local weighted least squares: Quadratic loess smoother

Feb 21 and 25: Local weighted least squares: Quadratic loess smoother Feb 1 and 5: Local weighted least squares: Quadratic loess smoother An example of weighted least squares fitting of data to a simple model for the purposes of simultaneous smoothing and interpolation is

More information

Comparing Variational, Ensemble-based and Hybrid Data Assimilations at Regional Scales

Comparing Variational, Ensemble-based and Hybrid Data Assimilations at Regional Scales Comparing Variational, Ensemble-based and Hybrid Data Assimilations at Regional Scales Meng Zhang and Fuqing Zhang Penn State University Xiang-Yu Huang and Xin Zhang NCAR 4 th EnDA Workshop, Albany, NY

More information

Suppression of impulse noise in Track-Before-Detect Algorithms

Suppression of impulse noise in Track-Before-Detect Algorithms Computer Applications in Electrical Engineering Suppression of impulse noise in Track-Before-Detect Algorithms Przemysław Mazurek West-Pomeranian University of Technology 71-126 Szczecin, ul. 26. Kwietnia

More information

Robust Estimation Methods for Impulsive Noise Suppression in Speech

Robust Estimation Methods for Impulsive Noise Suppression in Speech Robust Estimation Methods for Impulsive Noise Suppression in Speech Mital A. Gandhi, Christelle Ledoux, and Lamine Mili Alexandria Research Institute Bradley Department of Electrical and Computer Engineering

More information

5.1 2D example 59 Figure 5.1: Parabolic velocity field in a straight two-dimensional pipe. Figure 5.2: Concentration on the input boundary of the pipe. The vertical axis corresponds to r 2 -coordinate,

More information

TAKEHOME FINAL EXAM e iω e 2iω e iω e 2iω

TAKEHOME FINAL EXAM e iω e 2iω e iω e 2iω ECO 513 Spring 2015 TAKEHOME FINAL EXAM (1) Suppose the univariate stochastic process y is ARMA(2,2) of the following form: y t = 1.6974y t 1.9604y t 2 + ε t 1.6628ε t 1 +.9216ε t 2, (1) where ε is i.i.d.

More information